waite



H. F. WAITE.

X-RAY TUBE CURRENT MEASURING SYSTEM.

APPLICATION HLED JULY ll- I916- 1 ,307,.645 I Patented June 24, 1919.

i INVENTOR kiwi/1.716%? 'sTATEs PATENT QFFICE.

I HARRY F. WAITE, WHI'IESTONE LANDING, NEW YORK.

( x-RAY-T'UIBE CURRENT- MEASURING To all 'w/tom it may concern:

Be it known that I, HARRY FLIWAITE, a1

citizen of. the United States, and a resident of Whitestone Landing, county of Queens, city and State of New ,York, have inventeda newand useful Improvement in, X Ray- Tube Current-Measurin Systems, of which the following is a spec cation. 7 v

' The'object of my invention is to provide a simple, reliable and eflicient apparatus by which tube current may. always be accurately measured without danger to the operator and at a place most convenientto him. Heretofore such a current has been meas ured by an instrument laced in the pathvof the current that flows t rough the tube, that is the path of the rectified current as it has not been possible to obtain any measuring instrument which will accurately measure the:

minute alternating current which issues from the secondary of the transformer. By my invention, as hereinafter disclosed, it is osslble to measure tube current 1n any desired place and time without any risk tothe operator. This, and other objects are accomphshed by my invention, one embodiment gfwlhich is hereinafter more particularly set ort For a more particular description, refergenes is to be had to the accompanying drawmgs in which thefigure is a diagram'of my im roved system.

or clearness and con'cisens's of description my invention is. herein shown as ap-- plied to an alternating current system, itbeing understood that it may with equal facillt be applied to a. direct current system, t at is a system'in which the-primary current is derived from a direct current source instead of an alternating current source as herein disclosed.

The alternating current generator -1 has two brushes 2 and 3 respectively. The brush 2 runsto a wire 4- wh1ch is 'connected to the primary 5 of a-step-up transformer 6, in the conventional manner, and this'transformer'isalso conne cted -by a wire? to the brush 3. For convenience, all regulating instruments pole changers, etc., are left out of the description and drawing,-it'being un- Specification of Letters fatent. Patented J 119 24, 1919, Application filed July 11, 1916. Serial No. 108.602.

The secondary 8 of the transformer 6 has two leads '9 and 10 respectively,'which run to the rectifier 11, which may be a rotary rectifier or an other kind, as desired, and from this recti er 11 one wire 12 runs to the anode ,13 of the tube 14, and the other wire 15 is connected to the cathode, 16 of the tube 14.

The center winding of the secondary winding of the step-up transformer 6 is interrupt;

ed and a lead 17 runs therefrom to a wire 18 which is connected to a small step-down transformer 19- with its high tension coil 20 running to a second wire 21 which runs back to a lead 22 from the center coil of the secondary 8'of the step-up transformer 6, so

that the circuit-of the secondary 8 is always complete through the high tension coil 20 of the transformer 19, The low tension coil 23 of the transformer 19 is connected by two wires 24 and 25 respectively to the milliammeter. Thi's milliammeter 26 is calibrated so as to correspond with whatwould be shown if a milliammeter were placed in the circuit of the tube, say in the wire 12,

and the needle reads directly on the scale which is calibrated as just above indicated. 1

To prevent all stati charges the wire 18 is rounded by a suitable wire 27, as indicated.

he wire may be connected to the wire 7, if

desired.

In view of the foregoing, the operation of my improved system'will be readily understood. Assuming that'the apparatus is in use in. a normal manner, there will be a slight, but not a great current in the coil 20 of the small transformer 19, because the current in the seconda of the transformer 6, that is. the coil-8 is small. The minute current in the coil 20 generates a much stronger current .of a lower voltage in the coil 23,

, and this currentis sufiicient to actuate the milliammeter 26 so that this ammeter will read according to the volume of the current passing through the X-ray tube. As the tension in the wires 24 and 25 is always low it is possible to place thisinstrument 26 where most convenient to the operator, and it is impossible for-him to geta severe shock from it, This is not the-case where such an instrument is interposed in circuit with the wire 12' or with the .wire 15, in the conventiena'i' manner,

While I have shown and described .Oneembodiment of my invention, it isobvious that it is not restricted thereto, but is broad enough to cover all structures that come 5 Within the scope of the annexed claim.

' Having thus described my invention, What I claim is,

In a system of the lass described, a stepup transformer and means for energizing 10 the same, a secondary in said transformer connected to an X-ray tube, a step-down transformer with one coil connected to leads taken from the center of the secondary of the said step-up transformer, a low tension current coil in said step-down transformer and a meter connected therewith so that the volume of the current passlng through the X-ray tube may be read on said meter.

HARRY F. WVAITE. 

